Devices and methods for electronic analyte assaying

Abstract

An improved qualitative or semi-quantitative diagnostic test for measuring low levels of any analyte, such as hCG, in a biological sample, such as urine. The test comprises a test device containing reagents for the detection of the monitored analyte and an electronic reader that measures color development at a detection area of the device. The color development is converted to an electronic or digital signal. Improvements were made to the electronic reader to optimize the coverage of the detection area on the test strip. This improves the detection sensitivity and consistency of the test result while maintaining its reliability and accuracy.

What is claimed is: 
     
       1. A disposable analyte detection device comprising:
 a receiving member configured to receive a test strip comprising a test region and a background region laterally displaced along the length of said test strip; 
 a first plurality of sensors placed such that said first plurality of sensors are located above said test region once said test strip is received; 
 at least one background sensor placed such that said background sensor is located above said background region once said test strip is received; and 
 a light source placed such that said light source illuminates said test region and said background region once said test strip is received; and 
 a processor programmed to:
 receive test region signals indicating a quantity of light reflected from said test region from each of said first plurality of sensors; 
 receive background signals indicating a quantity of light reflected from said background region from said background sensor; and 
 generate a detection result based at least in part on a comparison of at least some of said received test region signals with at least some of said received background signals, 
 
 wherein the processor is programmed to receive test region signals and background signals over a period of time, and 
 wherein generating the detection result comprises, for a point during said period of time, combining a test region signal from one of said first plurality of sensors with a background signal and comparing said combination to a threshold. 
 
     
     
       2. The device of  claim 1 , wherein said first plurality of sensors includes two or three sensors. 
     
     
       3. The device of  claim 1 , further comprising a second background sensor, said second background sensor also placed such that said second background sensor is located above said background region once said test strip is received,
 wherein said received background signals include signals from said second background sensor, and 
 wherein generating said detection result comprises combining said test region signal from one of said first plurality of sensors with one of a background signal received from one of said background sensor or said second background sensor and comparing said combination to said threshold. 
 
     
     
       4. The device of  claim 3 , wherein the first plurality of sensors include a left test region sensor and a right test region sensor, and wherein the device includes a left background region sensor and a right background region sensor. 
     
     
       5. The device of  claim 4 , wherein the processor is programmed to generate said detection result by:
 subtracting said left test region sensor value from said left background region sensor value; 
 subtracting said right test region sensor value from said right background region sensor value; and 
 comparing said results to said threshold. 
 
     
     
       6. The device of  claim 4 , wherein the processor is programmed to generate said detection result by:
 subtracting said left test region sensor value from said right background region sensor value; 
 subtracting said right test region sensor value from said left background region sensor value; and 
 comparing said results to said threshold. 
 
     
     
       7. The device of  claim 1 , wherein at least one of said first plurality of sensors and said at least one background sensor include a photodetector. 
     
     
       8. A method of detecting an analyte, the method comprising:
 receiving, via a receiving member, a test strip comprising a test region and a background region laterally displaced along the length of said test strip; 
 illuminating, via a light source, said test region and said background region; 
 receiving, via a processor, test region signals indicating a quantity of light reflected from said test region included on the test strip from each of a first plurality of sensors; 
 receiving, via said processor, background signals indicating a quantity of light reflected from said background region included on said test strip from a background sensor; and 
 generating, via said processor, a detection result based on said received test region signals and said received background signals, 
 wherein receiving said test region signals and said background signals occurs over a period of time, and 
 wherein generating the detection result comprises, for a point during said period of time, combining a test region signal from one of said first plurality of sensors with a background signal and comparing said combination to a threshold. 
 
     
     
       9. The method of  claim 8 , wherein receiving said test region signals comprises receiving test region signals from two or three sensors. 
     
     
       10. The method of  claim 8  , wherein receiving said background signals further comprises receiving background signals from a second background sensor, and
 wherein generating said detection result comprises combining said test region signal from one of said first plurality of sensors with one of a background signal received from one of said background sensor or said second background sensor and comparing said combination to said threshold. 
 
     
     
       11. The method of  claim 10 , wherein the first plurality of sensors include a left test region sensor and a right test region sensor, and wherein the device includes a left background region sensor and a right background region sensor. 
     
     
       12. The method of  claim 11 , wherein generating said detection result comprises:
 subtracting said left test region sensor value from said left background region sensor value; 
 subtracting said right test region sensor value from said right background region sensor value; and 
 comparing said results to a threshold. 
 
     
     
       13. The method of  claim 11 , wherein generating said detection result comprises:
 subtracting said left test region sensor value from said right background region sensor value; 
 subtracting said right test region sensor value from said left background region sensor value; and 
 comparing said results to a threshold. 
 
     
     
       14. The method of  claim 8 , wherein receiving said test region signals from said first plurality of sensors and receiving said background signals from said at least one background sensor comprises receiving respective signals from photodetectors. 
     
     
       15. A disposable analyte detection device comprising:
 means for receiving a test strip comprising a test region and a background region laterally displaced along the length of said test strip; 
 means for illuminating said test region and said background region once said test strip is received; 
 means for receiving test region signals indicating a quantity of light reflected from said test region included on said test strip from each of a first plurality of sensors; 
 means for receiving background signals indicating a quantity of light reflected from said background region included on said test strip from a background sensor; and 
 means for generating a detection result based at least in part on a comparison of at least some of said received test region signals with at least some of said received background signals, 
 wherein receiving said test region signals and said background signals occurs over a period of time, and 
 wherein generating the detection result comprises, for a point during said period of time, combining a test region signal from one of said first plurality of sensors with a background signal and comparing said combination to a threshold.